Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  *  linux/fs/ext4/block_validity.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright (C) 2009
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  * Theodore Ts'o (tytso@mit.edu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  * Track which blocks in the filesystem are metadata blocks that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9)  * should never be used as data blocks by files or directories.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/time.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/namei.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <linux/quotaops.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <linux/buffer_head.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include <linux/swap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) #include <linux/pagemap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) #include <linux/blkdev.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #include "ext4.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) struct ext4_system_zone {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 	struct rb_node	node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 	ext4_fsblk_t	start_blk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 	unsigned int	count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 	u32		ino;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) static struct kmem_cache *ext4_system_zone_cachep;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) int __init ext4_init_system_zone(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	ext4_system_zone_cachep = KMEM_CACHE(ext4_system_zone, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	if (ext4_system_zone_cachep == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) void ext4_exit_system_zone(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 	rcu_barrier();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	kmem_cache_destroy(ext4_system_zone_cachep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) static inline int can_merge(struct ext4_system_zone *entry1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 		     struct ext4_system_zone *entry2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 	if ((entry1->start_blk + entry1->count) == entry2->start_blk &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 	    entry1->ino == entry2->ino)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 		return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) static void release_system_zone(struct ext4_system_blocks *system_blks)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	struct ext4_system_zone	*entry, *n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	rbtree_postorder_for_each_entry_safe(entry, n,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 				&system_blks->root, node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 		kmem_cache_free(ext4_system_zone_cachep, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65)  * Mark a range of blocks as belonging to the "system zone" --- that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66)  * is, filesystem metadata blocks which should never be used by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67)  * inodes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) static int add_system_zone(struct ext4_system_blocks *system_blks,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 			   ext4_fsblk_t start_blk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 			   unsigned int count, u32 ino)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 	struct ext4_system_zone *new_entry, *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 	struct rb_node **n = &system_blks->root.rb_node, *node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 	struct rb_node *parent = NULL, *new_node = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	while (*n) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 		parent = *n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 		entry = rb_entry(parent, struct ext4_system_zone, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 		if (start_blk < entry->start_blk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 			n = &(*n)->rb_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 		else if (start_blk >= (entry->start_blk + entry->count))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 			n = &(*n)->rb_right;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 		else	/* Unexpected overlap of system zones. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 			return -EFSCORRUPTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	new_entry = kmem_cache_alloc(ext4_system_zone_cachep,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 				     GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 	if (!new_entry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	new_entry->start_blk = start_blk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	new_entry->count = count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	new_entry->ino = ino;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	new_node = &new_entry->node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 	rb_link_node(new_node, parent, n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 	rb_insert_color(new_node, &system_blks->root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 	/* Can we merge to the left? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 	node = rb_prev(new_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	if (node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 		entry = rb_entry(node, struct ext4_system_zone, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 		if (can_merge(entry, new_entry)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 			new_entry->start_blk = entry->start_blk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 			new_entry->count += entry->count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 			rb_erase(node, &system_blks->root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 			kmem_cache_free(ext4_system_zone_cachep, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	/* Can we merge to the right? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	node = rb_next(new_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 	if (node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 		entry = rb_entry(node, struct ext4_system_zone, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 		if (can_merge(new_entry, entry)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 			new_entry->count += entry->count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 			rb_erase(node, &system_blks->root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 			kmem_cache_free(ext4_system_zone_cachep, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) static void debug_print_tree(struct ext4_sb_info *sbi)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	struct rb_node *node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 	struct ext4_system_zone *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	struct ext4_system_blocks *system_blks;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 	int first = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	printk(KERN_INFO "System zones: ");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	system_blks = rcu_dereference(sbi->s_system_blks);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	node = rb_first(&system_blks->root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	while (node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 		entry = rb_entry(node, struct ext4_system_zone, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 		printk(KERN_CONT "%s%llu-%llu", first ? "" : ", ",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 		       entry->start_blk, entry->start_blk + entry->count - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 		first = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 		node = rb_next(node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 	printk(KERN_CONT "\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) static int ext4_protect_reserved_inode(struct super_block *sb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 				       struct ext4_system_blocks *system_blks,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 				       u32 ino)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	struct inode *inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	struct ext4_sb_info *sbi = EXT4_SB(sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 	struct ext4_map_blocks map;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	u32 i = 0, num;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	int err = 0, n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	if ((ino < EXT4_ROOT_INO) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	    (ino > le32_to_cpu(sbi->s_es->s_inodes_count)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	inode = ext4_iget(sb, ino, EXT4_IGET_SPECIAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	if (IS_ERR(inode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 		return PTR_ERR(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 	num = (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	while (i < num) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 		cond_resched();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 		map.m_lblk = i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 		map.m_len = num - i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 		n = ext4_map_blocks(NULL, inode, &map, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 		if (n < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 			err = n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 		if (n == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 			i++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 		} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 			err = add_system_zone(system_blks, map.m_pblk, n, ino);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 			if (err < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 				if (err == -EFSCORRUPTED) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 					__ext4_error(sb, __func__, __LINE__,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 						     -err, map.m_pblk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 						     "blocks %llu-%llu from inode %u overlap system zone",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 						     map.m_pblk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 						     map.m_pblk + map.m_len - 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 						     ino);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 				}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 				break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 			}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 			i += n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 	iput(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) static void ext4_destroy_system_zone(struct rcu_head *rcu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 	struct ext4_system_blocks *system_blks;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 	system_blks = container_of(rcu, struct ext4_system_blocks, rcu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 	release_system_zone(system_blks);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 	kfree(system_blks);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205)  * Build system zone rbtree which is used for block validity checking.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207)  * The update of system_blks pointer in this function is protected by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208)  * sb->s_umount semaphore. However we have to be careful as we can be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209)  * racing with ext4_data_block_valid() calls reading system_blks rbtree
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210)  * protected only by RCU. That's why we first build the rbtree and then
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211)  * swap it in place.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) int ext4_setup_system_zone(struct super_block *sb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 	ext4_group_t ngroups = ext4_get_groups_count(sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 	struct ext4_sb_info *sbi = EXT4_SB(sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 	struct ext4_system_blocks *system_blks;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 	struct ext4_group_desc *gdp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 	ext4_group_t i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 	int flex_size = ext4_flex_bg_size(sbi);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 	system_blks = kzalloc(sizeof(*system_blks), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 	if (!system_blks)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 	for (i=0; i < ngroups; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 		cond_resched();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 		if (ext4_bg_has_super(sb, i) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 		    ((i < 5) || ((i % flex_size) == 0))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 			ret = add_system_zone(system_blks,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 					ext4_group_first_block_no(sb, i),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) 					ext4_bg_num_gdb(sb, i) + 1, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 			if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 				goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 		gdp = ext4_get_group_desc(sb, i, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) 		ret = add_system_zone(system_blks,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 				ext4_block_bitmap(sb, gdp), 1, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) 			goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 		ret = add_system_zone(system_blks,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) 				ext4_inode_bitmap(sb, gdp), 1, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 			goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 		ret = add_system_zone(system_blks,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 				ext4_inode_table(sb, gdp),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 				sbi->s_itb_per_group, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 			goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 	if (ext4_has_feature_journal(sb) && sbi->s_es->s_journal_inum) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 		ret = ext4_protect_reserved_inode(sb, system_blks,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) 				le32_to_cpu(sbi->s_es->s_journal_inum));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) 			goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) 	 * System blks rbtree complete, announce it once to prevent racing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) 	 * with ext4_data_block_valid() accessing the rbtree at the same
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) 	 * time.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) 	rcu_assign_pointer(sbi->s_system_blks, system_blks);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) 	if (test_opt(sb, DEBUG))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) 		debug_print_tree(sbi);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) err:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) 	release_system_zone(system_blks);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 	kfree(system_blks);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276)  * Called when the filesystem is unmounted or when remounting it with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277)  * noblock_validity specified.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279)  * The update of system_blks pointer in this function is protected by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280)  * sb->s_umount semaphore. However we have to be careful as we can be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281)  * racing with ext4_data_block_valid() calls reading system_blks rbtree
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282)  * protected only by RCU. So we first clear the system_blks pointer and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283)  * then free the rbtree only after RCU grace period expires.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) void ext4_release_system_zone(struct super_block *sb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) 	struct ext4_system_blocks *system_blks;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) 	system_blks = rcu_dereference_protected(EXT4_SB(sb)->s_system_blks,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) 					lockdep_is_held(&sb->s_umount));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 	rcu_assign_pointer(EXT4_SB(sb)->s_system_blks, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) 	if (system_blks)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) 		call_rcu(&system_blks->rcu, ext4_destroy_system_zone);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298)  * Returns 1 if the passed-in block region (start_blk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299)  * start_blk+count) is valid; 0 if some part of the block region
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300)  * overlaps with some other filesystem metadata blocks.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) int ext4_inode_block_valid(struct inode *inode, ext4_fsblk_t start_blk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) 			  unsigned int count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) 	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) 	struct ext4_system_blocks *system_blks;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) 	struct ext4_system_zone *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) 	struct rb_node *n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) 	int ret = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) 	if ((start_blk <= le32_to_cpu(sbi->s_es->s_first_data_block)) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) 	    (start_blk + count < start_blk) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) 	    (start_blk + count > ext4_blocks_count(sbi->s_es)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) 	 * Lock the system zone to prevent it being released concurrently
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) 	 * when doing a remount which inverse current "[no]block_validity"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) 	 * mount option.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) 	rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) 	system_blks = rcu_dereference(sbi->s_system_blks);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) 	if (system_blks == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) 		goto out_rcu;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) 	n = system_blks->root.rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) 	while (n) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) 		entry = rb_entry(n, struct ext4_system_zone, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) 		if (start_blk + count - 1 < entry->start_blk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) 			n = n->rb_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) 		else if (start_blk >= (entry->start_blk + entry->count))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) 			n = n->rb_right;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) 		else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) 			ret = (entry->ino == inode->i_ino);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) out_rcu:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) 	rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) int ext4_check_blockref(const char *function, unsigned int line,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) 			struct inode *inode, __le32 *p, unsigned int max)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) 	__le32 *bref = p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) 	unsigned int blk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) 	if (ext4_has_feature_journal(inode->i_sb) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) 	    (inode->i_ino ==
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) 	     le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_journal_inum)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) 	while (bref < p+max) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) 		blk = le32_to_cpu(*bref++);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) 		if (blk &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) 		    unlikely(!ext4_inode_block_valid(inode, blk, 1))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) 			ext4_error_inode(inode, function, line, blk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) 					 "invalid block");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) 			return -EFSCORRUPTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365)